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Cup Stacking is a free online sport stacking game. Piles of nested cups sit on a blue mat, and you upstack each pile into a pyramid, left to right, then downstack them all back into columns as fast as you can. Every cup is one press of a hand — F or the left arrow, J or the right arrow, or a tap on either half of the table — and the lit cup shows which. The catch is the wobble: put a cup on one that is still rocking and the stack comes down. Twelve stages run from 3-3-3 through 3-6-3, 6-6 and 1-10-1 to the full 72-cup cycle, with hand signs dropped halfway. No download, no sign-up, and it plays on phones with two thumbs.
How to play Cup Stacking
- Pick a stage. The cups start in nested piles on the front of the mat; the stage name says the sequence, such as 3-3-3 (three piles of three) or 3-6-3.
- Upstack every pile into a pyramid, left pile to right, then downstack every pyramid back into a nested pile, left to right. The clock starts on your first cup and stops when the last one lands.
- One cup lights up at a time and each cup is one press of a hand. A cup on the right of its row is the right hand’s (J or →), a cup on the left the left hand’s (F or ←), and a middle cup takes either. On a phone, tap the right or left half of the table, or the two big hand pads under it.
- Until stage 5 a sign on the lit cup says which hand it wants. From stage 5 some stages drop the signs, and you read the cup’s side of its row instead.
- Some cups wobble for a moment when they land. A cup on the bottom row stands on the table and is always safe, but a cup put on a wobbling cup — or on one still in the air — topples the stack. In a downstack every cup nests on the one before, so watch each one settle.
- A wrong hand freezes both hands for 1.5 seconds, twice that for a second wrong press in a row and three times for a third. A topple costs 1.5 seconds plus 0.15 for every cup in the pile while you fix it.
- Beat the stage’s one-star time to clear it and unlock the next; the two- and three-star times are faster. Press P to pause; switching tabs pauses too, and the clock waits.
Tips
- Bottom-row cups never topple. Put them down as fast as your hands allow and save your patience for the cups that go on top.
- In a downstack every cup after the first lands on the one before it. Glance at the last cup before each press: if it is still rocking, wait for it to stop, then go at once.
- A wrong hand costs more than any wobble wait. When the next cup is in the middle of its row, either hand will do — use the one that is not still holding a cup.
- On stages without hand signs, look at where the lit cup sits in its row before you look at the keys. Right of the middle is the right hand, every time.
- Two thumbs beat one finger on a phone: rest one thumb on each half of the table so neither hand has to travel.
- Your best time for each stage is saved. On the long sequences a clean run with no fumbles is usually faster than a rushed one with two.
FAQ
Is Cup Stacking free to play?
Yes. Cup Stacking is free to play online in your browser, with no download, no account and nothing to buy. All twelve stages are here and unlock in order.
What do 3-3-3, 3-6-3 and the cycle mean?
They are the sequences of sport stacking, named after the piles of cups. 3-3-3 is three piles of three cups, each built into a pyramid of two with one on top; 3-6-3 is twelve cups with a pyramid of six in the middle. 6-6 is two pyramids of six and 1-10-1 a single cup, a pyramid of ten four rows high and a single cup. The cycle runs 3-6-3, 6-6 and 1-10-1 back to back, which in this game is 72 cup moves.
Which hand do I press?
The one on the lit cup’s side. A cup on the right of its row is the right hand’s — J or the right arrow — and a cup on the left the left hand’s — F or the left arrow. A middle cup takes either hand. The first four stages show the hand on the cup; from stage 5 some stages leave the sign off and you read the cup’s side yourself.
Why did my stack topple?
You put a cup on one that was still moving. Some cups wobble for a moment when they land, and every cup is in the air for a split second after you press. A cup on the bottom row stands on the table and never topples, but a cup that goes on top of a wobbling or flying cup brings the pile down. A topple costs 1.5 seconds plus 0.15 seconds for every cup in the pile.
Can I just drum both keys as fast as I can?
It does not pay. The game deals the cups of each pile in a different order every run, so the hands do not simply take turns, and a wrong hand freezes you for longer each time in a row. We measured players who drum without looking, alternating or picking a hand at random, at every steady pace from 0.08 to 0.5 seconds a press over 41 runs: on every stage their middle run is slower than the one-star time.
How are the star times set?
They are measured, not guessed. Three simulated players — a casual, a regular and a sharp one — stack each stage 41 times, with a realistic tempo, the odd wrong hand, a reaction time and a chance of missing a wobble. One star is the time four in five casual players match or beat, two stars the regular player’s middle time and three stars the sharp player’s.
Is the timing the same whatever my screen’s frame rate?
Yes. Every press is timed from the moment it happened, and the wobbles and the clock run on time rather than on frames, so a 60 Hz phone and a 144 Hz monitor score the same presses the same way.
How is Cup Stacking different from Perfect Stack and Stack Sort?
Perfect Stack: Happy Tower is about timing a single tap to drop a sliding block, and Stack Sort is a calm sorting puzzle with no clock. Cup Stacking is a race against your own time with two hands: following the lit cup, pressing the right hand for it, and waiting just long enough for the cup underneath to settle.
Does Cup Stacking work on a phone or tablet?
Yes. Tap the left or right half of the table, or the two big hand pads under it — each press counts the instant your finger lands. Holding the phone with a thumb on each side works best.